Dust hood



(pa ented Feb. 7, 1939 UNITED STATES PATENT OFFICE DUST HOOD James H. Markley, Ramsey, N. J. Application September 24, 1936, Serial No. 102,311 13 Claims. ((31. 255-50) i "The invention relates to a dust hood which is adapted to be set over a hole being driven by a rock drill. The hood is connected with a dust v separating system of any desired form,which also it includes a suction means, so that the hood serves as. the primary dust collectlngdevicein a dust collecting system.

I :An object of the invention is to construct a dust hood for rock drills and the like which may io bepositioned over a hole being drilled and re- 7 moved from over the hole without removal of thedrill steel from the hole. With the drill steel still in the hole, the hood may be placedover the hole, or removed therefrom in order to inspect the le-"hole, by pressing or pulling the hood laterally with respect to the drill'steel. a Another object of the invention is to construct a hood for a rock drill in which the hood may be removed from over, the hole without withdrawing the drill steel from the hole merely by pulling the hood laterally with respect to the drill steel. The hood may be again positioned over the hole fby laterally moving the hood over the hole with the drill steel stillin the hole, and such hood forms 7 2 5. an effectiveseal against the escapeof dust from thehole. In addition, the hood is so constructed that aldrill steel with its enlarged head may be forced through the top of the housing, after which the top is effectively closed against the escape of all dust. I

Another object is to construct a dust hood for a' dust collecting system for rock drills which c has a yieldable side wall so that the hood may be inserted over the hole being drilled, or removed f from over the hole, withoutremovingthe drill steel from the hole and merely by pressing the drill steel shank through the yieldable'side, after I which the yieldable side wall closes to prevent the escape of dust therethrough. This side wall construction may also be associated with a construction enabling the drill steel to be inserted through the hood from the top thereof;

i Another object of the invention is to vprovide a e bafile within thehood which serves as another a -seal against the escape of dust from the hood when utilized with a gasket covering the open top, and also directs the suction of the dust 001- I lecting system more'directly to the mouth of the a 7 hole being drilled. The baffie may also be used so; alone'as the sole seal for the top of the hood. I

. Other" objects of the invention will be more apparent from the following description taken in 7 connection with the accompanying drawing illusi tin preferred e b m nts of the invention I as in which; I

Figure 1 is a plan view of the dust hood showing a top flexible gasket enabling a drill steel with its head substantially larger than the shank to be inserted therethrough, after which the hood is effectively closed against the escape of dust 5 therethrough. This view also shows part of the construction whereby the hood may be positioned over or removed from over the hole being drilled without removing the drill steel from the hole.

Figure 2 Ba side view of the hood showing the means in the side of the housing through which the shank of the drill steel may be inserted into the hood, after which the means closes to prevent the escape of dust therethrough. The hood may be removed from over the hole, with the drill steel still in the hole, through the means in the side of the housing. v

Figure 3 is a longitudinal section through the dust hood taken on line 3-.-.3 of Figure 1. This view also shows-a second flexible gasketor baille. 20

- Figure 4 is a bottom view of the dust hood looking in the inside thereof and showing the second flexible gasket or baflle, which may or may not be used, as desired, for further aiding the collection of, the dustas it emerges from the hole being drilled.

. Figure 5 is .airont view of another form of dust hood which may be inserted over the hole being drilled, or removed therefrom, without removing the drill steel from the hole. This hood will pass 3 the head or bit of a drill steel through the flexible top of the housing, after which the flexible top closes to prevent the escape of dust from the hood.

Ithasbeen vfound that with long drill steels, 5

and particularly the drill steels used on the wagon type of rock drills, it is inconvenient and results in lost time for the drill steel to b pulled out of theohole in order to remove the dust hood for i even raising it a particle. The dust hood also may be removed irorn over the hole when the drill steel is in operation, if desired, although so longas the head is removed from over the hole when the drill is in operation, dust is permitted to escape into the atmosphere. The hood may be again inserted over the hole without removing the drill steel from the hole by laterally returning the dust hood to its position over the hole. The dust hood also will permit the enlarged head or bit of a drill steel to be passed through the top of the hood, after which the top closes, except for the opening through which the drill steel projects,

to prevent the escape of dust from the hood. A

drill steel in the trade has a bit, which is the cutting head, and a shank which is the part of the drill steel which fits into the chock of the air hammer. The intermediate part apparently has no specific name, so the word shank is adopted to define that part of the drill steel including the bit or head. The drill steel may be of any desired size or shape.

The dust hood comprises a housing I I] which preferably is cylindrical, although it may be any form desired. A flexible sealing means, which is preferably a rubber gasket I I of substantial thickness, is secured to the top of the housing ID by any suitable means such as the ring I2 and'the bolts I3. A rubber gasket about three-quarters of an inch in thickness has been found suitable for this service. A connection I4 is provided in the housing which is adapted to be connected with any suitable dust collecting system having a suction means as part of its system. a

A drill steel hole I6 extends through the ru ber gasket and, in the form of dust hood illustrated, is located centrally of the hood. As will appear more fullyhereinafter, the central location of the hole I6 is not essential. Slots or slits I! extend radially from the hole l6 far enough so that the enlarged bit or head of a drill steel may be plunged through the gasket into the hood, after which the rubber gasket returns to its initial position sealing the top of the dust hood excepting for the drill steel hole Hi. The slots I1 are preferably slots which may permit a slight amount of air to pass therethrough, as distinguished from slits which would form a tight seal. However, either slits or slots are satisfactory. The hole I6 is of such a diameter that the drill steel shank may be freely rotatable therein. A tight fit is not essential, but a clearance of about a sixteenth to an eighth of an inch has been found satisfactory to seal the top of the hood against the escape of dust therethrough. The slots or slits I! are preferably so narrow that they seal themselves or substantially seal themselves against the escape of dust therethrough. Any number of slits I1 may be used and three are illustrated; V

Preferably wear plates I8 are secured to the gasketaround the opening I6 by means of the screws or bolts I9 to protectthe rubber gasket from being mutilated by the head of the drill steel. The wear plates also protect the drill steel opening against excessive wear which may result from the movement of the shank of the drill steel in the opening. Wear plates 20 are also preferably provided around the hole It upon the inner surface of the gasket.

A slit or slot 2| extends from the drill steel hole I6 to the outer periphery of the hood. Preferably the slit 2I has substantially bevelled edges 22 in order to render the rubber at this slit more yieldable or flexible. It will be observed that the yieldable sides of the slit or slot 2| will function as a yieldable passage to permit the shank of the drill steel to pass to the drill steel opening I6 irrespective of whether or not the other radial slots I! are provided in the top'gasket II. Again, the slot 2| will function to pass the shank of the drill steel therethrough, irrespective of what type or form of meansare used to permit the shank of the drill steel to pass through the sidewall of the housing III. As will appear in connection with the construction :of Figure 5, the slot 2| is all that is necessary to provide a yieldable passage which permits the hood to be inserted laterally over 'a rock hole being drilled by lateral movement of the hood with respect to the drill steel.

The slot or slit 2 I is flexible by virtue of it being formed in the flexible gasket II forming the cover for the top of the housing ID and in which is provided the drill steel opening I6. In another aspect of the invention illustrated and described, the drill steel opening is provided in the top of the housing in the gasket H and the flexible means forms a yieldable passage which extends from the side of the housing to the drill steel opening. This flexible means in the embodiments illustrated takes the form of flexible rubber sides for the slot 2|. Other constructions are contemplated for providing a flexible or yieldable passage for the drill steel through the top of the housing to the drill steel opening.

The side of the housing II] has an opening 24 extending from the top to the bottom of the housing or completely, through the side wall of the housing. Flexible sealing means is used tocover this opening, which flexible means permits entry of the shank of the drill steel through the side of' the housing and thereafter seals the opening against the escape of dust therethrough. This sealing means preferably comprisesa rubber gasket means made up of four flat pieces of rubber which extend from the bottom of the housing to the top thereof and engage or sub-' stantially engage the bottom of the top gasket II. Two of the rubber pieces 25 and 26 are secured to one side of the opening 24 in the housing I0 by means of the plate 21 and thescrews 28. The other two fiat rubber pieces 29 and 3B are secured to the other side of the opening 24 in the side of the housing I 0 by means of the plate 3| and the screws or bolts 32.

The flat rubber piece 25, forming part of the flexible means for the side opening, is wider than the flat rubber piece 29 so that 'the'slot 33, formed by their abutting edges, is not centrally located with respect to the opening 24. Similarly, the fiat rubber piece 30 is wider than the flat rubber piece 26 so that, the slot 34, formed by their abutting edges, is not centrally located withrespect to the opening 24. With the flat rubber pieces being of dissimilar width, the slots- 33 and 34 are spaced from each other so that an effective and positive seal against the escape of dust from the hood is provided by the flexible or gasket means'upon the side of the housing. Any other flexible sealing means is contemplated to form a yieldable passage to permit a drill steel shank to be pressed therethrough and thereafter seal the passage in the side of the housing.

In the form of housing particularly illustrated in Figures 1 through 4 of the'dr'awing, the side opening 24 in the housing I0 is shown as being approximately at the periphery of the cylindrical housing. It is to be understood that the side wall sealing means and the opening'24 may be located adjacent tothe edge of the drill steel opening or hole IE "or at any intermediate posi-' tion between these two positions. The shape of the housing, therefore, would be a segment of a cylinder, the cross-section of which is greater desired distance away therefrom.

.In many drilling operations the hole to be drilled in the rock is adjacent to a wall or other obstruction and where the hole is so located, the drilling is termedline or channel drilling. Where such lineor channel drilling is to be done, it is essential that the drill'steel hole IS in the top gasket of the hood beas close to the side wall of the hood as it is possible to bring it. One way to accomplish this is to have the side wall of the housing, formed by the sealing means 25, 26, 29 and 30, as'near to the drill steel l6 as it is possible to bring it. In every other respect, however, this line drilling hood is like the hood particularly illustrated in the drawing.

The slots 33 and 34 as'well as the slot 2| extending from the hole I6 .to the outer periphery ofthe hood enable a drill steel shank to be pressed through these slots to the central or drill steel hole It or to be removed from the drill steel hole merely by thepressure of the drill steel upon the side of the hood. It is evident,

therefore, that the drill steel need not be removed from the hole being drilled inthe rock in order a to remove the hood from around the drill steel so inverted cone.

that the hole may be inspected.

,i A baffle-4|i may be provided within the hood if desired. This baffle is preferably made of rubher and curves downwardly to a point adjacent thebottom of the hood where an opening 4| is provided for the drill steel shank in alignment with the drill steel hole IS in the top gasket The form of the baffle is substantiallythat of an The baffle has slots or slits 42 which enable the baffle to yield when the enlarged fdrill steel head is plunged therethrough and to return, to initial position around the smaller diameter of the shank of the drill steel. The bafile 40 is preferably removably retained within the housing I!) by means of a flanged ring or partial ring'43 which is held in place by screws 44;

The ring has an opening at the point where the side opening 24 is provided in the housing.

'The bafile 40 preferably is provided with a slot 45 which passes completely therethrough and is located in alignment with the long slot 2| in the top gasket and hence is in alignment with the entrance through the side opening 24 in the housing so that the shank of the drill steel may pass into the opening 2| merely by pressing the drill 1 steel against the flexible gaskets or sealing means at the side of the housing. The baffle 49 is preferably of softer rubber than the gasket I so that it willbe more flexible. The baffle 40 with the slot 45 passing therethrough also enables the bafile to be formed or cut from flat rubber and bent.

of dust through the top gasket and also applies the suction from the dust collecting system more 7 directly at the mouth of the hole being drilled. A dust hood without the baffle has been found entirely efficacious in preventing the escape of Again the baffle may,

dust from the drill hole.

be used alone without the top gasket H or as a I substitute therefor. The preferred construction, however, uses the top-gasket. where only one gasket or flexible means is used to close the top opening in the housing. 7 The hood described does notform a tight seal with the ground or working face at the bottom ofthe hood irrespective of the direction of the drilling operation. As a matter of fact, considerable space may be left underneath the head without sacrificing in any material respect the efficiency 6f the hood to collect the dust from the hole.

Thereis shown in Figure 5 a form of dust hood for rock'drills in which the top gasket serves both as a seal or cover for the open top of the housing and also as a seal or cover for the opening in theside of the housing. In this construction of hood, the housing 55 has its top directed at an incline or angle so that the top flange 5| merges with the bottom flange 52 at the opening 53 in the side of the housing.

The same gasket used with the dust hood illustrated in Figures 1 through 4 may be used to cover the top of the housing 50. The gasket issecured to the housing 59 by a ring 55 and the screws 56. In this construction the radially extending slot or slit 2|, which extends to the outer periphery of the gasket II, is positioned at the opening 53 in the side of the housing so that the drill steel shank may be passed through the slot 2| to the drill steel opening l6.

It may be desirable to form a gasket or flexible means particularly for this form of housing, instead of utilizing the gasket H. In such gasket the drill steel opening l6 would be formed in the rubber so that it would be normal to the bottom flange 52 of the housing 50 or at an angle to the surface of the gasket. Where the hole to be'drilled in the rock'is at an angle to the surface of the ground,'the gasket I would be better suited because the drill steel opening 5 would then be at an angle to the bottom flange 52 of the housing or at right angles to the inclined top flange 5|.

It will be observed, therefore, that in the constructionillustrated in Figure 5 a single means is provided for covering the top opening of the housing 50 and also for covering the side opening 53 in the side of the housing. In both constructions of hood, however, means are provided for covering the top of the housing and for covering the side opening in the housing against the escape of dust from the hood, and this means is so'constructed or provided with a passage that the drill steel can be passed through the side of the housing to the drill steel opening I6 without removing the drill steel from the hole. The drill steel is inserted into the housing through the side thereof merely by pressure of the drill steel against the side of the housing which opens up the hood or particularly the flexible means so that the drill steel will pass therethrough to the drill steel opening l6.

Various modifications will occur to those skilled in the art in the configuration, composition and disposition of the component elements going to make up the invention as a whole, as well as in the selective combination or application of the respective elements, and no limitation is intended by the phraseology of the foregoing description or illustrations in the accompanying drawing.

What is claimed is:

1. A dust hood for rock drills and the like using a drill steel having a shank comprising a housing having an open bottom, a drill steel opening in the top of the hood approximating the diameter of the drill steel shank, an opening in the side, and the periphery being rigid except at the opening; and flexible means forming a yieldable passage extending from the opening in the side of the housing to the drill steel opening to permit the shank of a drill steel to be inserted into and ing having a drill steel opening therein through removed from the drill steel opening through the side of the housing upon pressure being exerted thereagainst by the drill steel and thereafter close the passage against any substantial escape of dust therethrough, and a connection with the inside of the housing.

2. A hood for rock drills and the like using a drill steel having a shank comprising a housing having an open bottom, an open top, an opening in the side, and the periphery being rigid except at the opening; flexible means covering the open top and closing the opening in the side of the housing, the flexible means having a drill steel opening approximating the size of the shank of a drill steel, and a slot in the flexible means extending from the side of the housing to the drill steel opening to permit the shank of a drill steel to be laterally inserted into and removed from the drill steel opening through the opening in the side of the housing upon pressure being exerted thereagainst by the drill steel, and a connection with the inside of the housing.

3. A hood for rock drills and the like using a drill steel having a shank and enlarged head comprising a housing having an open bottom, an open top, an opening in the side, and the periphery being rigid except at the opening; flexible means covering the open top and closing the opening in the side of the housing, the flexible means having a drill steel opening approximating the size of" the shank of a drill steel, a slot in the flexible means extending from the side of the housing to the drill steel opening to permit the shank of a drill steel to be laterally inserted into and'removed from the drill steel opening through the opening in the side of the housing upon pres sure being exerted thereagainst by the drill steel, and a plurality of slots in the flexible means extending in a radial direction from the drill steel opening to permit the enlarged head of a drill steel to pass through the top of the hood; and a connection with the inside of the housing.

4. A hood for rock drills and the like using a I drill steel having a shank comprising a housing having an open bottom, a side opening, a rigid periphery except at the side opening, and a drill steel opening in the top thereof approximating the size of the shank of a drill steel through i which opening a drill steel is adapted to project,

means covering the side opening which opens to permit the shank of a drill steel to be inserted into and removed from the drill steel opening through the side of the housing upon pressure being exerted upon the means by the drill steel, and a connection with the inside of the housing.

5. A hood for rock drills comprising a housing having an open bottom, the housing having an opening in the side thereof, a top on the housing having a drill steel opening therein through which a drill steel is adapted to project, flexible sealing means covering the side opening so that the shank of a drill steel may be inserted laterally through the side of the housing to the drill steel opening and removed from the drill steel opening through the side opening including two rubber pieces, one rubber piece being secured to each side of the opening and extending from the top to the bottom thereof, the edge of the rubber piece on one side being in abutting relation with the edge of the other rubber piece, and a connection with the inside of the housing,

6. A hood for rock drills comprising a housing having an open bottom, the housing having an opening in the side thereof, a top on the housthe side opening;

which a drill steel is adapted to project; flexible sealing means covering the side opening so that the shank of a drill steel may be inserted laterally through the side of the housing to the drill steel opening and removed from the drill steel opening through the side opening including two pairs of rubber gaskets'of dissimilar width secured to each side. of the side opening in the housing and extending from the top to the bottom thereof, the edges of one pair of gaskets abutting the edges of'the other pair to seal the opening; and a connection with the inside of the housing. 7

'7. A hood for rock drills comprising a housing having an open bottom, a rigid periphery, and an opening in the side thereof; a top on the housing having a drill steel opening therethrough through which a drill steel is adapted to project, the drill steel opening being spaced from the side opening, flexible sealing means covering the side opening so that the shank of a drill'steel may be inserted through the side of the housing-to the drill steel opening and removed therefrom through the side opening, flexible sealing means in the top of the housing between the side opening and the drill steel opening so that the shank of a drill steel may be passed through the top flexible means to the drill steel opening, and a connection with the inside of the housing.

8. A hood for rock drills comprising a housing having an open bottom and an open top, means in the side of the housing so that the shank of a drill steel may be inserted through the side thereof to the top opening and removed through the side of the housing, a flexible sealing gasket means covering the top of the housing and having a drill steel opening therethrough through which a drill steel is adapted to project, the drill steel opening being spaced from the side of the housing, a slot in the flexible gasket extending between the means in' the side of the housing and the drill steel opening so that the shank of a drill steel may be passed throughthe slot to the drill steel opening, the gasket at the edges of the slot being bevelled to increase the flexibility, and a connection with the inside of the housing. 7

9. A hood for ,rock drills comprising a housing having a rigid periphery, an, open bottom, an open top, and an opening in the side thereof; flexible sealing means covering the side opening so that the shank of a drill steel may be inserted into the housing and removed therefrom through a flexible sealing gasket covering the top of the housing and having a drill steel opening therethrough through which a drill steel is adapted to project, the drill steel opening being spaced from the side opening, slots extending radially from the drill steel opening'so that a drill steel head may pass through the gasket, and one radial slot extending between the side opening and the drill steel opening so that the shank of a drill steel may be passed through the top sealing gasket to the drill steel opening; and a connection with the inside of the housing.

10. A hood for rock drills and the like using a drill steel having a shank and enlarged head comprising a housing having an open bottom, an open top and an opening in the side; a first flexible means covering the open top and closing the openingin the side of the housing, the flexible means having a drill steel opening approximating the size of the shank of a drill steel, a

slot extending from the side opening in the housing tothe drill steel opening in the flexible means to permit the shank of a drill steel to be laterally inserted into and removed from the drill steel opening through the side of the housingupon pressure being exerted thereagainst by the drill steel, a plurality of slots extending in a radial direction from the drill steel opening to permit 7 the head of a drill steel to pass through the top;

a flexible ballle means removably secured within the housing and below the first flexible means,

the flexible baffle means having a drill steeliopen- I ing approximating the size of the shank of a drill steel, and a plurality of slots extending ra- I dially from the opening to permit a drill steel head to pass therethrough; and a connection xwith the inside of the housing.

head to pass therethrough; and a connection with the inside of the housing.

' steel opening approximating the size of the shank I of a drill steel, a plurality of slots extending in a radial direction from the drill steel opening to permit the head of a drill steel to pass through the top; a flexible bafile means secured within the housing and below the first flexible means the flexible bafile means having a drill steel open- 7 ing approximating the size of the shank of a drill steel, and a plurality of slots extendingradially from the drill steel opening to permit a drill steel 12. A hood for rock drills and the like using a drill steel having a shank and enlarged head comprising a housing having an open bottom, and an open top; a flexible means within the housing for sealing the same against the escape of dust from the open top, the flexible means curving downwardly in the form of an inverted cone to a point adjacent the bottom of the housing, the flexible means having a drill steel opening approximating the size of the shank of a drill steel, a plurality of slots extending in a radial direction from the drill steel opening to permit the head of a drill steel to pass therethrough; and a connection with the inside of the housing.

13. A hood for rock drills and the like using a drill steel having a shank comprising a housing having an open bottom, an open top, and the top of the housing being at an angle with the bottom and merging therewith to form an opening in the side; flexible gasket means covering the open top and closing the opening in the side of the housing, the flexible means having a drill steel opening approximating the size of the shank of a drill steel, and a slot extending from the side opening in the housing to the drill steel opening in the flexible means to permit the shank of a drill steel to be laterally inserted into and removed from the drill steel opening through the opening in the side of the housing upon pressure being exerted thereagainst by the drill steel.

JAMES H. MARKLE'Y. 

